<ti-upload
  type="block"
  url="url"
  method="post"
  accept=".png,.jpg"
  alias="customFileName"
  [headers]="customHeaders"
  [formData]="customFormData"
  [formDataFirst]="false"
  (beforeSendItems)="beforeSendItems($event)"
>
</ti-upload>
<br />
<button class="mt-3 mb-3" type="button" tiButton (click)="changeHeaders()">增加头信息</button>
<demo-log [logs]="myLogs"></demo-log>
